A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5990-01-259-7138
NSN 5855-00-832-7316
NSN 6320-01-276-4739
NSN 6685-00-416-7103
NSN 5999-00-576-9942
NSN 5930-01-308-3989
NSN 5945-00-201-0956
NSN 5915-01-608-9318
NSN 4140-01-423-1647
NSN 5895-01-027-0746
NSN 5925-00-431-3256
NSN 5950-01-032-1997